
       
 html { overflow: hidden; }
 #demo {
    display: block;
    border: 1px solid #000;
    }
*{
    font-family: '微软雅黑';
    font-weight: bold;
}
            
 #box{
    background-color: cornflowerblue;
    height: 60px;
    width: 510px;
    margin: 0 auto;
    margin-top: 20px;
    }
            
#t_1{
                
    }
            
.t_class{
    color: darkgrey;
    float: left;
    height: 60px;
    width: 100px;
    border-right:2px solid darkgrey;
/* background-color: black*/
    text-align: center;
    line-height: 60px;
    }
            
.t_bg{
    position: absolute;
    height: 60px;
    width: 100px; 
    z-index: 0;
    background-color: rgba(10%,20%,30%,0.7);
    display: none;
    }
            
label{
    z-index: 1;
    color: #ffffff;
    }